This is a continuation-in-part of application Ser. No. 09/682,300, filed Aug. 16, 2001, and which is included in its entirety herein by reference.
1. Field of the Invention
The present invention relates to a printhead cartridge for an inkjet printer. In particular, the present invention discloses a tape automated bonding (TAB) device for a printhead cartridge, the TAB device having an asymmetrical contact distribution and an offset printhead location that enable a size reduction of a corresponding flexible circuit board (FCB) within the printer.
2. Description of the Related Art
Please refer to FIG. 1A. FIG. 1A is a perspective view of a prior art TAB 14 disposed on an inkwell 12 of a printhead cartridge 10. The inkwell 12 is used to hold ink (not shown) for printing. The TAB 14 wraps around from a front surface 15 to a bottom surface 19 of the inkwell 12. The TAB 14 comprises a plurality of contacts 16, each with a corresponding trace 17 that electrically connects the contact 16 to a printhead 18. The printhead 18 is mounted on the TAB 14, and is situated on the bottom surface 19 of the inkwell 12. The TAB 14 is substantially symmetrical with respect to a centerline Axe2x80x94A of the printhead cartridge 10. Specifically, the plurality of contacts 16 are evenly distributed on both sides of the line Axe2x80x94A, and the longitudinal centerline of the printhead 18 is coincident with the line Axe2x80x94A.
Referring to FIG. 1B and FIG. 1C, the printhead cartridge 10 is installed in and controlled by a printer 100. The printer 100 comprises a flexible circuit board (FCB) 102 (not shown in FIG. 1B) to establish electrical contact with the plurality of contacts 16 of the TAB 14, so that the printhead cartridge 10 can receive signals from the printer 100. The printhead 18 performs a printing operation by jetting ink supplied from the inkwell 12 according to the signals received from the contacts 16. Moreover, the FCB 102 accommodates two printhead cartridges 10 disposed side-by-side in the printer 100.
The symmetrical arrangement of the plurality of contacts 16 and the printhead 18 on the TAB 14 can result in an FCB that is unnecessarily large and costly, that is, the prior art design is inefficient.
It is therefore a primary objective of the claimed invention to provide a tape automated bonding (TAB) device having an asymmetrical distribution of contacts and an offset printhead location to reduce a size of a corresponding contact surface within a printer.
Briefly summarized, the preferred embodiment of the claimed invention TAB device includes a tape having a region capable of being substantially bisected by a centerline that defines a first side of the tape and a second side of the tape. Disposed on the tape is a printhead, and a plurality of contacts adapted to receive signals from the printer and to provide the signals to the printhead. The contacts are disposed such that the number of contacts on the first side is different from the number of contacts on the second side.
According to the claimed invention, the printhead can be centrally aligned with the centerline or centrally offset from the centerline. Additionally, if the printhead is centrally offset from the centerline the plurality of contacts can be symmetrically equally distributed across the centerline.
It is an advantage of the claimed invention that the asymmetric distribution of contacts and the centrally offset printhead location allow for a significantly smaller flexible circuit board (FCB) in the printer. This results in a reduced cost of manufacture for the printer.
These and other objectives of the claimed invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.